One of the best game I have ever played in a long time.
-Story line: Engaging and paced. Never feels like you are outside of the HP world, even if you wonder off to some random villages. You can at any moment wonder off to a rather interesting side quest or just b-line it to the end of the story line. The only issue is that if you do not do side quests you do not have some very useful spells.
-Attention to detail: My god did they put in a great effort! Every corner, every knob, every brick has something to say in Hogwarts. Even in Hogsmead and the rest of the map, you will be surprised to find meticulousness and "magic" infused everywhere.
-Combat: Pretty fun system. Almost feels like you are playing a fighting game with wands. A lot of interesting combos and ways to cleverly beat opponents. I also love the RPG style, where potions and items give you a small edge on the final results. All in all, even though one cannot compare it to a dedicated MMORPG game, there is quite some detail and minmaxing you can put on combat builds.
-Quiddich: Noooooooooo 😯. They did not include it. Broom (and <<SPOILER ALERT>> other magical animals) flying is nice but I was looking forward to play some quidditch. A bummer but I will be waiting for it in the next game!
To sum up! Buy it, play it, enjoy it! I haven't had this much fun in a game since God of War.